Words have power. Not like Harry Potter, not magical. But within the human brain different words have different effects. Take two words with identical definitions, but the meaning is slightly different. One evokes darker thoughts than the other. One implies implies benevolent of malevolent intent. Politicians, advertisers, and news agencies are always being careful to pick words that make people think certain ways about certain topics. The choice of word changes how people think and can cause changes in brain chemistry. But, according to the book, it goes deeper. Those who know how words work can manipulate your brain. Like moving tumblers in a lock, the right combination of syllables can open a mind to outright control. At the heart of this book is a school and organization where they teach people how to use the words and then use them on the world.
The book is broken into four parts. For the first two parts, the story alternates chapter by chapter between a homeless girl with an inate talent for manipulation who gets selected for the school and a guy kidnapped from an airport because they think he's resistant to the control words. After that the book becomes a bit more disorderly and jumps all over in time.
This isn't new. It's interesting, but I saw it done in "Soon I Will Be Invincible". But in this book it helps obscure where the story is going. Enough TV and reading will cause a person to start to anticipate in stories. You can figure the orphan child is going to become the chosen one who will eventually smite Darth Voldamort or whoever. This book manages to throw the reader off the trail repeatedly, without all the trauma that comes with storyline shifts in Game of Thrones.
I've already loaned this book out. I suggest you read it, too.